Simplify the following expression: $x = \dfrac{4z + 3}{4z - 3} - \dfrac{8z + 13}{4z - 3}$
Explanation: Since the expressions have the same denominator we simply subtract the numerators: $x = \dfrac{4z + 3 - (8z + 13)}{4z - 3}$ Distribute the negative sign: $x = \dfrac{4z + 3 - 8z - 13}{4z - 3}$ Combine like terms: $x = \dfrac{-4z - 10}{4z - 3}$